Side by side

Sinn U18vsZelos Spearfish 3

The numbers, the dial colors, the calibers — laid out so you can stop flipping between tabs.

U18
SinnU18
MSRP $3,488
Spearfish 3
ZelosSpearfish 3
MSRP $749
What people say

Owners + reviewers, side by side

Synthesized for each watch independently from owner discussions, enthusiast forums, written reviews, and video reviewers.

Sinn U18

The Sinn U18 is praised for its unique deep blue/green dial with three-dimensional oxygen bubbles that change with light, and its comfortable, easily adjustable bracelet. Owners find the watch stunning and a piece of history, appreciating the refined hands. The Sinn U18 features a 44mm, 15.5mm thick case made from German submarine steel, offering a 2000-meter dive specification and Sinn's Ar-Dehumidifying technology, powered by a Sellita SW300-1 movement. The case thickness is apparent, and the watch comes as a complete set with box and papers for $3,000-$3,680. On balance, owners and reviewers rate the Sinn U18 highly for its striking dial and robust build.

Zelos Spearfish 3

The Zelos Spearfish 3 is widely praised for its exceptional finishing, with razor-sharp polish and flawless brushed transitions that owners feel exceed its price point. The 40mm case is noted for its wearability, and the La Joux-Perret G100 movement offers a 68-hour power reserve, with reported accuracy averaging +2.6 seconds per day. Reviewers highlight the exceptionally smooth bi-directional bezel and a tool-less micro-adjustment clasp described as best-in-class among microbrands. The sapphire sandwich construction and lumed bezel are also cited as desirable features. Overall, owners and reviewers rate the Zelos Spearfish 3 highly for its outstanding finishing and value at its price point.

At a glance

15 of 29 specs differ
Diameter
U1844mm
Spearfish 340mm
Power Reserve
U1842h
Spearfish 340h
Water Resistance
U182,000m
Spearfish 3200m
MSRP
U18$3,488
Spearfish 3$749

Full specifications

Case

8 specs
Diameter
44mm
40mm
Thickness
15.5mm
11.5mm
Lug-to-Lug
40mm
Lug Width
22mm
20mm
Material
high-strength
316L Stainless Steel
Finish
Brushed and polished
Water Resistance
2000m
200m
Caseback
Solid

Crystal & Dial

4 specs
Crystal Shape
Flat
AR Coating
Inner
Dial Color
Black
Diver - Forged Carbon
Indices
Applied

Movement

2 specs
Caliber
SW300-1
La Joux-Perret G100
Power Reserve
42h
40h

Pricing

1 specs
MSRP
$3,488
$749
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